X-ZrO2 addition (X= Ce, La, Y and Sm) on Ni/MgAl2O4 applied to methane tri-reforming for syngas production

• Published in: Journal of CO2 utilization 2019-10, Vol.33, p.273-283
• Main Authors: Paladino Lino, Ananda Vallezi, Assaf, Elisabete Moreira, Assaf, José Mansur
• Format: Article
• Language: English
• Subjects: Basicity; Coke; Methane; Spinel; Synthesis gas
• ISSN: 2212-9820; 2212-9839
• DOI: 10.1016/j.jcou.2019.06.016

•Ce-ZrO2 on MgAl2O4 support increased CH4 and CO2 conversions and products yields.•H2/CO ratio (syngas quality) was at around 2, proper to Fischer-Tropsch synthesis.•Catalysts apparent dispersion seems related to non-strong base sites concentration. Nickel supported on MgAl2O4 spinel (Ni/MA) and the effects of X-ZrO2 (X = Ce, La, Sm and Y) addition to the support were studied in Methane Tri-Reforming (MTR) process. The characterization techniques employed were XRD, B.E.T., H2-TPR, H2-TPD, CO2-TPD, XPS, and in situ XANES. The presence of lanthanides and Y associated to ZrO2 modified the Ni0 dispersion and the surface basicity. These properties influence the coke formation, which increased as the metallic dispersion diminished. Ce-ZrO2 association on the spinel support led to the greatest catalytic performance, increasing reactants conversions due to its adequate base properties that allowed the adsorption of new reactants molecules due to coke elimination, associated to its smallest apparent Ni0 average size. Moreover, the Ce-Zr support favored the NiO activation, without compromising the nickel dispersion.